F#, Split String and .Net methods
I'm new to F#. I'm using VS2008 shell and F# interactive. I try to split a string using "System.String.Split" but then I get the error: "Split is not a static method"
code example:
开发者_JAVA百科let Count text =
let words = System.String.Split [' '] text
let nWords = words.Length
(nWords)
How do I use the String methods like split in F# ?
You call them as instance methods:
let Count (text : string) =
let words = text.Split [|' '|]
let nWords = words.Length
(nWords)
(Note you need to use [| |]
because Split takes an array not a list; or, as per Joel Mueller's comment, because Split takes a params array, you can just pass in the delimiters as separate arguments (e.g. text.Split(' ', '\n')
).)
The function String.split is now defined in the F# Power Pack. You must add
#r "FSharp.PowerPack.dll";;
#r "FSharp.PowerPack.Compatibility.dll";;
See the errata for Expert F#: http://www.expert-fsharp.com/Updates/Expert-FSharp-Errata-Jan-27-2009.pdf
Get FSharp.PowerPack.dll here: http://fsharppowerpack.codeplex.com/
Using .NET member functions:
let count (text : string) =
text.Split [|' '|]
|> Seq.length
Or using FSharpx
, which gives us more ergonomic free-functions...
paket.dependencies
source https://api.nuget.org/v3/index.json
nuget FSharpx.Extras 2.3.2
paket.references
FSharpx.Extras
Usage:
open FSharpx
let count (text : string) =
text
|> String.splitChar [| ' ' |]
|> Seq.length
Note that F# Power Pack seems to be deprecated.
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